Post-disaster reconstruction is a topic of global concern,and traditional villages have special heritage attributes and need to face more requirements and obstacles in post-disaster reconstruction.This paper summarize...Post-disaster reconstruction is a topic of global concern,and traditional villages have special heritage attributes and need to face more requirements and obstacles in post-disaster reconstruction.This paper summarizes four concepts based on the research on post-disaster reconstruction both domestically and internationally,as well as the recovery and reconstruction of cultural heritage.Through a field survey of traditional villages in the Ms 6.8 Luding earthquake-stricken area,it is found that there are problems such as insufficient awareness of heritage value,misalignment of scientific reconstruction technology,and insufficient protection of reconstruction elements during the reconstruction process.Traditional villages face the risk of declining or even loss of heritage value.In order to effectively protect traditional villages and inherit the carrier of regional culture,four targeted reconstruction response strategies are proposed,i.e.,to"establish special planning for traditional village preservation","emphasize recovery of the authenticity of village heritage","ensure elements for village heritage recovery"and"promote the activation and utilization of village heritage",based on the problems discovered during the survey and the four concepts summarized in the research on post-disaster reconstruction of traditional villages.The research results hope to provide useful reference for ancient cultural areas affected by earthquakes on how to protect cultural heritage during the post-disaster reconstruction process.展开更多
Through the introduction of disaster situation of Qiang Culture after Wenchuan Earthquake, the paper emphasized that carriers of Qiang Culture had been seriously damaged, the inheritance of Qiang Culture had been affe...Through the introduction of disaster situation of Qiang Culture after Wenchuan Earthquake, the paper emphasized that carriers of Qiang Culture had been seriously damaged, the inheritance of Qiang Culture had been affected, and the environment for Qiang Culture was difficult to recover. It highlighted that three-dimensional reconstruction of Qiang Culture should stress the core task and timely and effectively rescue endangered cultural heritages of Qiang Nationality from the perspectives of material and spiritual life. It had explained focuses of three-dimensional pattern construction in detail. In terms of spatial reconstruction, it should reconstruct native culture and history while material culture was constructed, and reconstruct Qiang culture highland by depending on aborigines; in terms of cluster reconstruction, it should give support to large tourism enterprises and perfect tourism chain; in terms of ecological reconstruction, it should enhance construction and demonstration of "ecological protection pilot area of Qiang culture"; in terms of development reconstruction, it should realize coordinated unity between protection and development according to classification protection, characteristic protection and key protection, so as to form the virtuous circle of post-disaster recovery protection and sustainable development.展开更多
The 2008 Wenchuan earthquake in Sichuan of China was the result of quake-triggering along an active several hundred-kilometer-long fault. The subsequent landslides and debris flow geohazards are dominating factors in ...The 2008 Wenchuan earthquake in Sichuan of China was the result of quake-triggering along an active several hundred-kilometer-long fault. The subsequent landslides and debris flow geohazards are dominating factors in planning post-disaster recovery and rebuilding. This paper presents recommendations for coping with large-scale geohazards and disasters. It is essential to establish a national emergency management system for huge scale catastrophe and earthquake precursor identification. Town construction must be kept away from active faults, especially to improve town safety in areas with high risk of seismic and geological hazards, and it is important to improve geohazard investigation and remediation for mountain areas that have become loosened by earthquake activity. Geological factors must be better understood to reduce direct and secondary risks and effects of earthquakes. Site selections for public relocation require clear and informed analysis of geological and social risk reduction, so that relocation, infrastructure reconstruction, and commemorative relic-sites can be protected.展开更多
To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken areas.However,spatiotemporal...To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken areas.However,spatiotemporal evolution and its driving factors of urban land in earthquake-prone areas remains limited due to the scarcity of ground observation data.This research,leveraging night-time light remote sensing imagery and land cover data,conducted a comprehensive analysis of the long-term evolution characteristics of urban land in earthquake-prone areas.It introduced methodologies for assessing the socio-economic impact and the primary natural environmental factors driving urban land evolution in these regions.To validate the proposed methods,the 2008 Wenchuan earthquake-affected area in China was selected as a representative study area.The results indicated that the average Digital Number(DN)values in socio-economically impacted areas showed a trend of rising,falling,and then rising again after the earthquake.DN values in three types of damaged areas including Type Ⅱ,Type Ⅲ,and Type Ⅳ exceeded pre-earthquake levels.The analysis of determinative factors influencing urban land evolution revealed that slope and elevation were key elements in controlling urban land expansion before the earthquake,whereas factors such as slope,elevation,lithology,and faults had a stronger influence on urban land expansion after the earthquake.It can be seen that,in view of the differences in the natural conditions of regions for post-disaster reconstruction,the local government need to actively adjust and adapt to urban spatial planning,so as to leverage the scale effect of large-scale inputs of funds,facilities,human resources and other factors after the disaster,thus enhancing resilience and recovery efficiency in response to disaster impacts.展开更多
Natural disasters provide an acute image of how man-made technologies are a cause of conflict when it comes to nature. It is man versus wild in its true means. The nature lets us grow and increase our settlements. We ...Natural disasters provide an acute image of how man-made technologies are a cause of conflict when it comes to nature. It is man versus wild in its true means. The nature lets us grow and increase our settlements. We encroach on other animals' territories and it is only when the environment's patience runs out that it retaliates in forms of natural disasters. These disasters affect numerous lives and kill a lot ofhnmans. This is the main reason why we require more stable structures and preventive measures to battle the wrath of the nature. Rescue and search operations are conducted by many different government and private agencies including NGOs. These operations aim at providing the required relief and supplies after the disaster. Injured people need to be treated. People in dangerous zones need to be evacuated. Help is needed in many forms. Out of the many natural disasters, this paper will focus on the occurrence of earthquakes. Severe earthquakes destroy buildings and structures like roads, bridges etc. and wreak havoc in the community. Earthquakes largely damage all human constructions, including houses. This is the reason why a reconstruction program for dwellings and housings is of utmost importance. A home is only secondary to basic needs such as food and water. A well-planned strategy is important when it comes to launching a post-earthquake reconstruction program. The strategy should be reasonable and should consider the best interests of everyone affected; self-help and imported fabrication should play no part in the decision-making procedures. Creating awareness, physically demonstrating options and delivering are the three steps for the success of reconstruction programs. The extent of affected area and the magnitude of earthquakes are variable in nature and it is on these two aspects that the reconstruction strategy is devised. Technical aspects are focused towards the development of the affected areas and conceptual design of surrounding neighborhoods. It also aims at identifying seminars and programs based on easy financing for a new home. Along with these, review processes are conducted for the analysis of new residential needs based on optimizing the use of available land for planning and development. The paper discusses the construction of housing and resettlements as prioritized activities that must be undertaken post an earthquake. Earthquakes physically only destroy structures and buildings but for the people affected, they destroy lives, jobs, companies, sources of food and the sense of safety and traumatize the ones who come out alive.展开更多
On May 12, 2008 at 14:28, a catastrophic magnitude M 8.0 earthquake struck the Sichuan Province of China. The epicenter was located at Wenchuan (31.00°N, 103.40°E). Liquefaction macrophenomena and corresp...On May 12, 2008 at 14:28, a catastrophic magnitude M 8.0 earthquake struck the Sichuan Province of China. The epicenter was located at Wenchuan (31.00°N, 103.40°E). Liquefaction macrophenomena and corresponding destruction was observed throughout a vast area of 500 km long and 200 km wide following the earthquake. This paper illustrates the geographic distribution of the liquefaction and the relationship between liquefaction behavior and seismic intensity, and summarizes the liquefaction macrophenomena, including sandboils and waterspouts, ground subsidence, ground fissures etc., and relevant liquefaction features. A brief summary of the structural damage caused by liquefaction is presented and discussed. Based on comparisons with liquefaction phenomena observed in the 1976 Tangshan and 1975 Haicheng earthquakes, preliminary analyses were performed, which revealed some new features of liquefaction behavior and associated issues arising from this event. The site investigation indicated that the spatial non-uniformity of liquefaction distribution was obvious and most of the liquefied sites were located in regions of seismic intensity VIII. However, liquefaction phenomena at ten different sites in regions of seismic intensity VI were also observed for the first time in China mainland. Sandboils and waterspouts ranged from centimeters to tens of meters, with most between 1 m to 3 m. Dramatically high water/sand ejections, e.g., more than 10 m, were observed at four different sites. The sand ejections included silty sand, fine sand, medium sand, course sand and gravel, but the ejected sand amount was less than that in the 1976 Tangshan earthquake. Possible liquefaction of natural gravel soils was observed for the first time in China mainland.展开更多
Land suitability assessment (LSA) is one of the key processes of land-use planning. Given its particularity of land suitability assessment for post-earthquake reconstruction, this paper takes into account geological...Land suitability assessment (LSA) is one of the key processes of land-use planning. Given its particularity of land suitability assessment for post-earthquake reconstruction, this paper takes into account geological conditions, risk of disasters, water and land resources conditions, and eco-environmental suitability and emphasizes safety factor in the assessment. Taking the April 20, 2013 Mw 6.6 Lushan earthquake as a case, this assessment establishes factors system, uses GIS spatial analysis techniques and data of geology, topography, resources, and eco-environment to evaluate the land suitability for reconstruction. The results show that: (1) the spatial characteristics of land suitability for reconstruction at grid scale and administrative scale manifest that most of the piedmont plains in the east are suitable for large-scale population aggregation, industrialization, and urbanization development; and (2) for the six hard-hit counties, Mingshan is the preferred region for large-scale post-earthquake reconstruction due to its high construction index and suitable land per capita, and some plots of land in the valleys could be selected for in-situ small-scale reconstruction in Lushan. The land suitability assessment for post-earthquake reconstruction would be significant to making sound reconstruction planning for achieving sustainable regional development in the Mw 6.6 Lushan earthquake stricken area. This study could be used as a reference for the regions with similar events.展开更多
This paper examines the experiences of two mountain communities- Yinchanggou and Donghekou in the Wenchuan earthquake of May 12, 2008, where Yinchanggou's tourism economy and natural park system was destroyed and ...This paper examines the experiences of two mountain communities- Yinchanggou and Donghekou in the Wenchuan earthquake of May 12, 2008, where Yinchanggou's tourism economy and natural park system was destroyed and Donghekou was buried by a landslide. We conducted research surveys on both the communities, interviewing survivors and local officials, and observed the destruction/reconstruction, geological, and living conditions. We suggest that protracted educational processes be put into place so that mountain communities possess a knowledge base to consider long-term disaster prevention when building the economy in the fragile and geo-hazardous conditions of the Longmenshan. The Donghekou Earthquake Ruins Park is an exemplar of turning disaster into sustainable, safe development for small mountain villages.展开更多
The pattern evolution and dynamic mechanism of the dynamic changes of regional gravity fields occurring before and after the Wenchuan Ms8.0 earthquake are analyzed, based on five epochs of 1998 -2007 mobile gravity da...The pattern evolution and dynamic mechanism of the dynamic changes of regional gravity fields occurring before and after the Wenchuan Ms8.0 earthquake are analyzed, based on five epochs of 1998 -2007 mobile gravity data from the middle-south section of the north-south seismic belt, and two epochs of field research data collected after the 2008 Wenchuan earthquake in combination with GPS data, leveling observations, and geotectonic environment data. The regional dynamic gravity changes demonstrate the effects of the eastward flow of solid matter in the Qinghai-Tibetan plateau and the preparation of the 2008 Wenchuan earthquake (2- 10 yr). The two most meaningful gravity indicators of the Wcnchuan earthquake preparation are the positive (increasing) gravity changes occurring over many years in the southwest epicenter and the largescale gradient zone of gravity variation, with the cumulative difference between the two sides of the gradient zone of gravity exceeding 200 μGal. The positive gravity changes may facilitate a constant energy accumulation and the gradient belt may support seismic shear breakage. Overall, the gravity changes associated with the earthquake preparation indicate a pattern of accelerating increase-decelerating increase-earthquake occurrence. The Songpan-Ganzi block generally displays a negative gravity change, providing evidence for a local upwarp- ing of the deep crust-mantle and an interior expansion of the deep crust attributable to high temperatures. The viewpoint is consistent with the dilatant mechanism for earthquake preparation.展开更多
The border areas of the Tibetan Plateau and the neighboring mountainous areas have a high incidence of earthquakes with a magnitude greater than M<sub>s</sub> 5.0, as well as having a dense distribution of...The border areas of the Tibetan Plateau and the neighboring mountainous areas have a high incidence of earthquakes with a magnitude greater than M<sub>s</sub> 5.0, as well as having a dense distribution of geological disasters such as collapses, landslides, and debris flows. Revealing the post-disaster economic development and recovery process is very important for enhancing disaster prevention and response capacity in order to formulate control policies and recovery methods for post-disaster economic reconstruction based on economic resilience. Using long-term socioeconomic data and the autoregressive integrated moving average (ARIMA) model, this paper calculated the economic resilience index of the areas most severely affected by the Wenchuan Earthquake of 2008 and adopted the improved variable returns to scale (VRS) date envelopment analysis (DEA) model and the Malmquist productivity index to analyze the efficiency and effect of annual post-disaster recovery. The results show that: (1) the economic resilience index of the areas most severely affected by the Wenchuan Earthquake was 0.877. The earthquake resulted in a short-term economic recession in the affected areas, but the economy returned to pre-quake levels within two years. In addition, the industrial economy was less resilient than agriculture and the service industry. (2) The comprehensive economic recovery efficiency of the disaster-stricken area in the year following the disaster was 0.603. The comprehensive efficiency, the pure technical efficiency, and the scale efficiency of the plain and hilly areas were significantly greater than those of the plateau and mountain areas. (3) The annual fluctuation in total factor productivity (TFP) following the disaster was considerable, and the economic recovery efficiency decreased significantly, resulting in a short-term economic recession. The TFP index returned to steady state following decreases of 33.7% and 15.2%, respectively, in the two years following the disaster. (4) The significant decrease in the post-disaster recovery efficiency was caused mainly by technological changes, and the renewal of the production system was the leading factor in determining the economic resilience following the disaster. With the decline in the scale of economic recovery following the earthquake, long-term economic recovery in the disaster-stricken areas depended mainly on pure technical efficiency, and the improvement in the latter was the driving force for maintaining the long-term growth of the post-disaster economy. Therefore, according to the local characteristics of natural environment and economic system, the disaster-stricken areas need to actively change and readjust their economic structures. At the same time, attention should be paid to updating the production system to enhance the level of technological progress and give full play to the scale effects of large-scale capital, new facilities, human resources, and other investment factors following the disaster so as to enhance the impact of economic resilience and recovery efficiency in response to the disaster.展开更多
Earth observation is an effective technique that plays an important role in earthquake damage reduction and reconstruction.This paper introduces the results of dynamic analysis on monitoring and assessing heavily impa...Earth observation is an effective technique that plays an important role in earthquake damage reduction and reconstruction.This paper introduces the results of dynamic analysis on monitoring and assessing heavily impacted areas affected by the Wenchuan Earthquake using remote sensing data acquired in the past 3 years from 2008 to 2010.Immediately after the disaster on 12 May 2008,the Chinese Academy of Sciences launched a project entitled‘Wenchuan Earthquake Disasters Monitoring and Assessment Using Remote Sensing Technology.’More than 400 images from 17 satellites and 20.2TB airborne remote sensing data were acquired to facilitate quick monitoring and evaluation of severely damaged areas in 14 counties.Results of the image analyses were forwarded on a timely basis to assist with consultative service and decisionmaking support.In subsequent years,in order to monitor the process of environmental restoration and reconstruction,airborne optical remote sensing images covering most of the severely damaged areas were again acquired in May 2009 and April 2010.These images were analyzed and compared along with images from 2008.Results were useful in support of further work on environmental protection and reconstruction in earthquake-damaged areas.Three typical areas were selected for illustrative purposes including Tangjiashan Barrier Lake,Beichuan County,and counties of Yingxiu and the new Beichuan.These results well demonstrate the importance and effectiveness of the utility of earth observation for disaster mitigation and reconstruction.展开更多
Assessment of population carrying capacity is a key task in the reconstruction planning of areas struck by disasters, in which the precision of estimation is required. This study developed a decision-making model for ...Assessment of population carrying capacity is a key task in the reconstruction planning of areas struck by disasters, in which the precision of estimation is required. This study developed a decision-making model for estimating the population capacity of the involved townships and cities in the 2008 Wenchuan Earthquake based on the assessment of the suitability for reconstruction of the areas. Through analysis, arable land resources were argued to be the critical constraint of population capacity in these areas. Then, the spatial differentiations of the post-quake development conditions across different regions were analyzed with respect to their natural environments, socio-economic development and quake damages. The expected levels of urbanization, family incomes and income structures, output levels of land, and the reliance of agricultural population on arable land were estimated by different regions. With these parameters, the population capacities of the involved townships and cities in three scenarios were estimated. The total population capacity of the entire areas is abundant compared with the actual post-quake population; however, the status of over-population substantially varies across space. It was suggested to put the emphasis of post-quake resettlement policy on those counties where earthquake had been the main causes of over-population. In the Full Recovery Scenario, three mountain counties were identified including Wenchuan, Beichuan and Maoxian, with a total over-population of about 100,000 people.展开更多
基金funded by the National Natural Science Foundation of China under the project“Research on Urban Spatial Coupling Mechanism Between Urban Epidemic Spreading and Vulnerability and Planning Response in Chengdu-Chongqing Area”(Grant No.52078423)the Major Program of Sichuan Provincial Scientific Research under the Project“Research and Demonstration of Resilient Collaborative Planning and Design for Park Cities”(Grant No.2020YFS0054)the Sichuan Provincial Science and Technology Innovation Platform and Talent Plan"Research on the Construction and Development Strategies of Several Major Infrastructure Systems for New Smart Cities"(Grant No.2022JDR0356).
文摘Post-disaster reconstruction is a topic of global concern,and traditional villages have special heritage attributes and need to face more requirements and obstacles in post-disaster reconstruction.This paper summarizes four concepts based on the research on post-disaster reconstruction both domestically and internationally,as well as the recovery and reconstruction of cultural heritage.Through a field survey of traditional villages in the Ms 6.8 Luding earthquake-stricken area,it is found that there are problems such as insufficient awareness of heritage value,misalignment of scientific reconstruction technology,and insufficient protection of reconstruction elements during the reconstruction process.Traditional villages face the risk of declining or even loss of heritage value.In order to effectively protect traditional villages and inherit the carrier of regional culture,four targeted reconstruction response strategies are proposed,i.e.,to"establish special planning for traditional village preservation","emphasize recovery of the authenticity of village heritage","ensure elements for village heritage recovery"and"promote the activation and utilization of village heritage",based on the problems discovered during the survey and the four concepts summarized in the research on post-disaster reconstruction of traditional villages.The research results hope to provide useful reference for ancient cultural areas affected by earthquakes on how to protect cultural heritage during the post-disaster reconstruction process.
文摘Through the introduction of disaster situation of Qiang Culture after Wenchuan Earthquake, the paper emphasized that carriers of Qiang Culture had been seriously damaged, the inheritance of Qiang Culture had been affected, and the environment for Qiang Culture was difficult to recover. It highlighted that three-dimensional reconstruction of Qiang Culture should stress the core task and timely and effectively rescue endangered cultural heritages of Qiang Nationality from the perspectives of material and spiritual life. It had explained focuses of three-dimensional pattern construction in detail. In terms of spatial reconstruction, it should reconstruct native culture and history while material culture was constructed, and reconstruct Qiang culture highland by depending on aborigines; in terms of cluster reconstruction, it should give support to large tourism enterprises and perfect tourism chain; in terms of ecological reconstruction, it should enhance construction and demonstration of "ecological protection pilot area of Qiang culture"; in terms of development reconstruction, it should realize coordinated unity between protection and development according to classification protection, characteristic protection and key protection, so as to form the virtuous circle of post-disaster recovery protection and sustainable development.
基金supported by the National Basic Research Program of the Ministry of Science and Technology of the People’s Republic of China (973 Project, Grant No. 2008CB425801)
文摘The 2008 Wenchuan earthquake in Sichuan of China was the result of quake-triggering along an active several hundred-kilometer-long fault. The subsequent landslides and debris flow geohazards are dominating factors in planning post-disaster recovery and rebuilding. This paper presents recommendations for coping with large-scale geohazards and disasters. It is essential to establish a national emergency management system for huge scale catastrophe and earthquake precursor identification. Town construction must be kept away from active faults, especially to improve town safety in areas with high risk of seismic and geological hazards, and it is important to improve geohazard investigation and remediation for mountain areas that have become loosened by earthquake activity. Geological factors must be better understood to reduce direct and secondary risks and effects of earthquakes. Site selections for public relocation require clear and informed analysis of geological and social risk reduction, so that relocation, infrastructure reconstruction, and commemorative relic-sites can be protected.
基金Foundation of China(Grant No.U21A2032)National Natural Science Foundation of China(Grant No.42371203).
文摘To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken areas.However,spatiotemporal evolution and its driving factors of urban land in earthquake-prone areas remains limited due to the scarcity of ground observation data.This research,leveraging night-time light remote sensing imagery and land cover data,conducted a comprehensive analysis of the long-term evolution characteristics of urban land in earthquake-prone areas.It introduced methodologies for assessing the socio-economic impact and the primary natural environmental factors driving urban land evolution in these regions.To validate the proposed methods,the 2008 Wenchuan earthquake-affected area in China was selected as a representative study area.The results indicated that the average Digital Number(DN)values in socio-economically impacted areas showed a trend of rising,falling,and then rising again after the earthquake.DN values in three types of damaged areas including Type Ⅱ,Type Ⅲ,and Type Ⅳ exceeded pre-earthquake levels.The analysis of determinative factors influencing urban land evolution revealed that slope and elevation were key elements in controlling urban land expansion before the earthquake,whereas factors such as slope,elevation,lithology,and faults had a stronger influence on urban land expansion after the earthquake.It can be seen that,in view of the differences in the natural conditions of regions for post-disaster reconstruction,the local government need to actively adjust and adapt to urban spatial planning,so as to leverage the scale effect of large-scale inputs of funds,facilities,human resources and other factors after the disaster,thus enhancing resilience and recovery efficiency in response to disaster impacts.
文摘Natural disasters provide an acute image of how man-made technologies are a cause of conflict when it comes to nature. It is man versus wild in its true means. The nature lets us grow and increase our settlements. We encroach on other animals' territories and it is only when the environment's patience runs out that it retaliates in forms of natural disasters. These disasters affect numerous lives and kill a lot ofhnmans. This is the main reason why we require more stable structures and preventive measures to battle the wrath of the nature. Rescue and search operations are conducted by many different government and private agencies including NGOs. These operations aim at providing the required relief and supplies after the disaster. Injured people need to be treated. People in dangerous zones need to be evacuated. Help is needed in many forms. Out of the many natural disasters, this paper will focus on the occurrence of earthquakes. Severe earthquakes destroy buildings and structures like roads, bridges etc. and wreak havoc in the community. Earthquakes largely damage all human constructions, including houses. This is the reason why a reconstruction program for dwellings and housings is of utmost importance. A home is only secondary to basic needs such as food and water. A well-planned strategy is important when it comes to launching a post-earthquake reconstruction program. The strategy should be reasonable and should consider the best interests of everyone affected; self-help and imported fabrication should play no part in the decision-making procedures. Creating awareness, physically demonstrating options and delivering are the three steps for the success of reconstruction programs. The extent of affected area and the magnitude of earthquakes are variable in nature and it is on these two aspects that the reconstruction strategy is devised. Technical aspects are focused towards the development of the affected areas and conceptual design of surrounding neighborhoods. It also aims at identifying seminars and programs based on easy financing for a new home. Along with these, review processes are conducted for the analysis of new residential needs based on optimizing the use of available land for planning and development. The paper discusses the construction of housing and resettlements as prioritized activities that must be undertaken post an earthquake. Earthquakes physically only destroy structures and buildings but for the people affected, they destroy lives, jobs, companies, sources of food and the sense of safety and traumatize the ones who come out alive.
基金National Natural Science Foundation of China Under Grant No.50638010 the Foundation of Ministry of Education for Innovation Group Under Grant No. IRT0518
文摘On May 12, 2008 at 14:28, a catastrophic magnitude M 8.0 earthquake struck the Sichuan Province of China. The epicenter was located at Wenchuan (31.00°N, 103.40°E). Liquefaction macrophenomena and corresponding destruction was observed throughout a vast area of 500 km long and 200 km wide following the earthquake. This paper illustrates the geographic distribution of the liquefaction and the relationship between liquefaction behavior and seismic intensity, and summarizes the liquefaction macrophenomena, including sandboils and waterspouts, ground subsidence, ground fissures etc., and relevant liquefaction features. A brief summary of the structural damage caused by liquefaction is presented and discussed. Based on comparisons with liquefaction phenomena observed in the 1976 Tangshan and 1975 Haicheng earthquakes, preliminary analyses were performed, which revealed some new features of liquefaction behavior and associated issues arising from this event. The site investigation indicated that the spatial non-uniformity of liquefaction distribution was obvious and most of the liquefied sites were located in regions of seismic intensity VIII. However, liquefaction phenomena at ten different sites in regions of seismic intensity VI were also observed for the first time in China mainland. Sandboils and waterspouts ranged from centimeters to tens of meters, with most between 1 m to 3 m. Dramatically high water/sand ejections, e.g., more than 10 m, were observed at four different sites. The sand ejections included silty sand, fine sand, medium sand, course sand and gravel, but the ejected sand amount was less than that in the 1976 Tangshan earthquake. Possible liquefaction of natural gravel soils was observed for the first time in China mainland.
基金National Natural Science Foundation of China,No.41301121,No.41430636,No.41171449Science and Technology Service Network Initiative of the Chinese Academy of Sciences,No.KFJ-EW-STS-003The Key Research Program of the Chinese Academy of Sciences,No.KZZD-EW-06-01
文摘Land suitability assessment (LSA) is one of the key processes of land-use planning. Given its particularity of land suitability assessment for post-earthquake reconstruction, this paper takes into account geological conditions, risk of disasters, water and land resources conditions, and eco-environmental suitability and emphasizes safety factor in the assessment. Taking the April 20, 2013 Mw 6.6 Lushan earthquake as a case, this assessment establishes factors system, uses GIS spatial analysis techniques and data of geology, topography, resources, and eco-environment to evaluate the land suitability for reconstruction. The results show that: (1) the spatial characteristics of land suitability for reconstruction at grid scale and administrative scale manifest that most of the piedmont plains in the east are suitable for large-scale population aggregation, industrialization, and urbanization development; and (2) for the six hard-hit counties, Mingshan is the preferred region for large-scale post-earthquake reconstruction due to its high construction index and suitable land per capita, and some plots of land in the valleys could be selected for in-situ small-scale reconstruction in Lushan. The land suitability assessment for post-earthquake reconstruction would be significant to making sound reconstruction planning for achieving sustainable regional development in the Mw 6.6 Lushan earthquake stricken area. This study could be used as a reference for the regions with similar events.
基金supported by China National Natural Science Foundation (Grants No. 40841010, 40972083)
文摘This paper examines the experiences of two mountain communities- Yinchanggou and Donghekou in the Wenchuan earthquake of May 12, 2008, where Yinchanggou's tourism economy and natural park system was destroyed and Donghekou was buried by a landslide. We conducted research surveys on both the communities, interviewing survivors and local officials, and observed the destruction/reconstruction, geological, and living conditions. We suggest that protracted educational processes be put into place so that mountain communities possess a knowledge base to consider long-term disaster prevention when building the economy in the fragile and geo-hazardous conditions of the Longmenshan. The Donghekou Earthquake Ruins Park is an exemplar of turning disaster into sustainable, safe development for small mountain villages.
基金financially supported by the National Natural Science Foundation of China (40574012,40374031)Key Project of the National Science & Technology Pillar Program in the Eleventh Five-year Plan(2006BAC01B02-02)Monitoring Project of China Earthquake Administration (201210)
文摘The pattern evolution and dynamic mechanism of the dynamic changes of regional gravity fields occurring before and after the Wenchuan Ms8.0 earthquake are analyzed, based on five epochs of 1998 -2007 mobile gravity data from the middle-south section of the north-south seismic belt, and two epochs of field research data collected after the 2008 Wenchuan earthquake in combination with GPS data, leveling observations, and geotectonic environment data. The regional dynamic gravity changes demonstrate the effects of the eastward flow of solid matter in the Qinghai-Tibetan plateau and the preparation of the 2008 Wenchuan earthquake (2- 10 yr). The two most meaningful gravity indicators of the Wcnchuan earthquake preparation are the positive (increasing) gravity changes occurring over many years in the southwest epicenter and the largescale gradient zone of gravity variation, with the cumulative difference between the two sides of the gradient zone of gravity exceeding 200 μGal. The positive gravity changes may facilitate a constant energy accumulation and the gradient belt may support seismic shear breakage. Overall, the gravity changes associated with the earthquake preparation indicate a pattern of accelerating increase-decelerating increase-earthquake occurrence. The Songpan-Ganzi block generally displays a negative gravity change, providing evidence for a local upwarp- ing of the deep crust-mantle and an interior expansion of the deep crust attributable to high temperatures. The viewpoint is consistent with the dilatant mechanism for earthquake preparation.
基金Second Tibetan Plateau Scientific Expedition and Research Program(STEP),No.2019QZKK0406National Natural Science Foundation of China,No.41807510,No.41501139。
文摘The border areas of the Tibetan Plateau and the neighboring mountainous areas have a high incidence of earthquakes with a magnitude greater than M<sub>s</sub> 5.0, as well as having a dense distribution of geological disasters such as collapses, landslides, and debris flows. Revealing the post-disaster economic development and recovery process is very important for enhancing disaster prevention and response capacity in order to formulate control policies and recovery methods for post-disaster economic reconstruction based on economic resilience. Using long-term socioeconomic data and the autoregressive integrated moving average (ARIMA) model, this paper calculated the economic resilience index of the areas most severely affected by the Wenchuan Earthquake of 2008 and adopted the improved variable returns to scale (VRS) date envelopment analysis (DEA) model and the Malmquist productivity index to analyze the efficiency and effect of annual post-disaster recovery. The results show that: (1) the economic resilience index of the areas most severely affected by the Wenchuan Earthquake was 0.877. The earthquake resulted in a short-term economic recession in the affected areas, but the economy returned to pre-quake levels within two years. In addition, the industrial economy was less resilient than agriculture and the service industry. (2) The comprehensive economic recovery efficiency of the disaster-stricken area in the year following the disaster was 0.603. The comprehensive efficiency, the pure technical efficiency, and the scale efficiency of the plain and hilly areas were significantly greater than those of the plateau and mountain areas. (3) The annual fluctuation in total factor productivity (TFP) following the disaster was considerable, and the economic recovery efficiency decreased significantly, resulting in a short-term economic recession. The TFP index returned to steady state following decreases of 33.7% and 15.2%, respectively, in the two years following the disaster. (4) The significant decrease in the post-disaster recovery efficiency was caused mainly by technological changes, and the renewal of the production system was the leading factor in determining the economic resilience following the disaster. With the decline in the scale of economic recovery following the earthquake, long-term economic recovery in the disaster-stricken areas depended mainly on pure technical efficiency, and the improvement in the latter was the driving force for maintaining the long-term growth of the post-disaster economy. Therefore, according to the local characteristics of natural environment and economic system, the disaster-stricken areas need to actively change and readjust their economic structures. At the same time, attention should be paid to updating the production system to enhance the level of technological progress and give full play to the scale effects of large-scale capital, new facilities, human resources, and other investment factors following the disaster so as to enhance the impact of economic resilience and recovery efficiency in response to the disaster.
基金supported by National Basic Research Program of China(973 Program,Nos.2009CB723906,2009CB723902)National 863 Program(2009AA12Z102).
文摘Earth observation is an effective technique that plays an important role in earthquake damage reduction and reconstruction.This paper introduces the results of dynamic analysis on monitoring and assessing heavily impacted areas affected by the Wenchuan Earthquake using remote sensing data acquired in the past 3 years from 2008 to 2010.Immediately after the disaster on 12 May 2008,the Chinese Academy of Sciences launched a project entitled‘Wenchuan Earthquake Disasters Monitoring and Assessment Using Remote Sensing Technology.’More than 400 images from 17 satellites and 20.2TB airborne remote sensing data were acquired to facilitate quick monitoring and evaluation of severely damaged areas in 14 counties.Results of the image analyses were forwarded on a timely basis to assist with consultative service and decisionmaking support.In subsequent years,in order to monitor the process of environmental restoration and reconstruction,airborne optical remote sensing images covering most of the severely damaged areas were again acquired in May 2009 and April 2010.These images were analyzed and compared along with images from 2008.Results were useful in support of further work on environmental protection and reconstruction in earthquake-damaged areas.Three typical areas were selected for illustrative purposes including Tangjiashan Barrier Lake,Beichuan County,and counties of Yingxiu and the new Beichuan.These results well demonstrate the importance and effectiveness of the utility of earth observation for disaster mitigation and reconstruction.
基金National Key Technology R&D Program of China, No.2008BAK50B05Knowledge Innovation Project of the Chinese Academy of Sciences, No.KZCX-YW-Q06 No.KZCX2-YW-Q03-06
文摘Assessment of population carrying capacity is a key task in the reconstruction planning of areas struck by disasters, in which the precision of estimation is required. This study developed a decision-making model for estimating the population capacity of the involved townships and cities in the 2008 Wenchuan Earthquake based on the assessment of the suitability for reconstruction of the areas. Through analysis, arable land resources were argued to be the critical constraint of population capacity in these areas. Then, the spatial differentiations of the post-quake development conditions across different regions were analyzed with respect to their natural environments, socio-economic development and quake damages. The expected levels of urbanization, family incomes and income structures, output levels of land, and the reliance of agricultural population on arable land were estimated by different regions. With these parameters, the population capacities of the involved townships and cities in three scenarios were estimated. The total population capacity of the entire areas is abundant compared with the actual post-quake population; however, the status of over-population substantially varies across space. It was suggested to put the emphasis of post-quake resettlement policy on those counties where earthquake had been the main causes of over-population. In the Full Recovery Scenario, three mountain counties were identified including Wenchuan, Beichuan and Maoxian, with a total over-population of about 100,000 people.